JP4138282B2 - Method for manufacturing organic electroluminescence element - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention is organicElectroluminescenceelement(Hereinafter organic EL Element, also called organic light-emitting element)Related to the manufacturing method.
[0002]
[Prior art]
An organic light emitting element (organic EL element or the like) emits light by attaching electrodes composed of an anode and a cathode on both sides of an organic insulator thin film having strong fluorescence and applying a DC voltage. Specifically, positive charges are injected from the anode (cathode electrode) and negative charges are injected from the cathode (anode electrode), and they move in the thin film by the applied electric field. Positive and negative charges moving through the thin film recombine with a certain probability, and the energy released upon recombination is consumed to form a singlet excited state (molecular exciton) of the fluorescent molecule. Molecular excitons emit light to the outside at the rate of their luminescence quantum efficiency and return to the ground state. A light emitting display and a laser element are manufactured using the light emitted at this time as EL light emission.
[0003]
The organic insulator thin film includes, for example, an electron transport layer, an electron injection layer, a light emitting layer, a hole transport layer, a hole injection layer, and the like, and is collectively referred to as an organic EL layer. Also, metal materials such as Al, Mg, and Ag are usually used for the cathode electrode, and transparent electrodes such as ITO (indium tin oxide) are often used for the anode electrode to extract EL light emission. . In many cases, a buffer layer is formed between each of the cathode and anode electrodes and the organic EL layer.
[0004]
As a method for forming a constituent element of an organic insulator thin film using a low molecular material, there is a vacuum deposition method using a metal mask in combination. On the other hand, a spin coating method is famous as a forming method using a polymer material. In the vacuum deposition method using a metal mask, each organic EL layer is generally formed in the same pattern on the substrate on which the anode electrode is patterned, and further, the cathode electrode is formed in another pattern. As an example of patterning using a metal mask, a 33 μm × 100 μm pattern was reported as of November 2000 (at the Symposium “From Organic EL to Organic Transistor”). The spin coating method is a method of forming an organic EL layer having a uniform film thickness by dissolving a polymer material in a solvent, dropping the solution onto a substrate, and rotating the substrate at a predetermined rotation speed.
[0005]
In recent years, an organic EL layer has been formed in advance on the surface of a support such as a PET (Polyethylene Terephthalate) film together with a heat propagation layer (also used as a release layer) (hereinafter referred to as a donor film), and this is applied to the substrate. There has been proposed a film forming method (hereinafter referred to as a thermal transfer method) in which stripe patterning is possible by scanning a laser from the back side of the support.
[0006]
[Problems to be solved by the invention]
However, in the vapor deposition method using the above-described metal mask, it is necessary to use a mask every time an organic EL layer, an anode electrode, or a cathode electrode is manufactured, and the resolution is limited due to the difficulty in aligning the mask and processing the mask itself. In addition, there are problems such as non-uniform pixel dimensions due to combined use with the vacuum deposition method, high cost and poor throughput due to the use of the vacuum deposition apparatus. In addition, in device fabrication using the spin coating method, pixel separation within the same plane cannot be achieved, and the selectivity of the polymer material for the organic EL layer due to the use of a solvent is a problem.
[0007]
On the other hand, the use of a thermal transfer method eliminates the need for a metal mask, and by preparing a film in which a polymer material is laminated in advance, patterning that is impossible with spin coating becomes possible. However, this method has a problem that it is difficult to produce a pattern other than the stripe pattern due to the difficulty of stability and controllability of the laser light source.
Furthermore, although there is a publication that simultaneously patterns the organic EL layer and the cathode (Japanese Patent Laid-Open No. 11-260549), there is a problem such as thermal damage to the organic EL film, and a large breakthrough is required for practical use of the device It is said.
[0008]
[Means for Solving the Problems]
  Thus, according to the present invention, there is provided a method of manufacturing a light emitting device including at least a first electrode, an organic layer including a light emitting layer, and a second electrode on a substrate, wherein the first electrode is provided on the substrate including the first electrode. 10 from electrodes ^-2 ~ Ten ^-Five cal / cm ・ s ・ ℃In the rangeAn organic film having a predetermined pattern with low thermal conductivity is formed, an organic layer is placed on the first electrode and the organic film, and the organic layer is transferred onto the first electrode but not transferred onto the organic film. Forming an organic layer on the first electrode in alignment with the first electrode by a thermal transfer methodConsists of
The organic film is formed on the substrate as a self-assembled monomolecular film by irradiating ultraviolet rays through a mask with a predetermined pattern and selectively adsorbing low molecular weight materials only in the ultraviolet irradiation region.Organic characterizedElectroluminescenceAn element manufacturing method is provided.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, in order to form an organic layer including a light emitting layer in a self-aligned manner on a substrate (for example, a glass substrate, a resin substrate, a semiconductor substrate) provided with a first electrode in advance, for example, lithography technology or self-organization. Patterns of organic films made of general-purpose polymers (for example, acrylic resins, epoxy resins, urethane resins, xylene resins, etc.), low molecular materials exemplified below, etc. are formed using a modified monomolecular film creation technology This is one of the features.
[0010]
When the organic layer including the light emitting layer is thermally transferred onto the substrate, a temperature of 100 to 350 ° C. is generated at the transfer film / substrate interface, depending on the transfer conditions. In forming an organic light emitting device, it is very important to control the behavior of the generated heat. The reason is that many organic substances are basically inferior in heat resistance. Here, thermal conductivity k (cal / cm · s. · ° C.) is one of the important parameters in utilizing the thermal properties due to the difference in materials. When the temperature distribution is in a steady state, the heat flux q passing through a unit area plane perpendicular to the heat flow direction (x axis) per unit time is a temperature gradient.
(DT / dx)
Proportional to
q = k (dT / dx)
It is expressed. If the temperature is in an unsteady state (for example, when the temperature changes with time), the temperature at each point is expressed by the following equation.
σT / σt = k / ρc · (σ²T / σx²)
[0011]
  Here, T: temperature, x: position, t: time, ρ: density, c: specific heat. Thermal conduction in a solid consists of conduction electrons and propagation of atomic thermal vibrations. The heat conduction by the former is dominant in the metal etc., but the heat conduction by the latter occurs in the insulator.
k = cρul / 3
It becomes. Here, u: speed of sound, l: mean free path of lattice vibration. According to previous experiments, for example, the thermal conductivity of ITO is 2.5 × 10^-2(Cal / cm · s · ° C), but 4.8 to 5.0 × 10 for acrylic resin^-FourThe value was about (cal / cm · s · ° C).
  In the present invention, the thermal conductivity of the organic film is higher than that of the first electrode., 10^-2~Ten^-FiveLow in cal / cm · s · ° C rangeYes.
[0012]
In the present invention, an organic film is formed on a substrate provided with a first electrode of an organic light emitting element (the first electrode is an anode made of, for example, ITO or a cathode made of an electrode (Al, Mg, etc.)). A predetermined pattern is formed. A donor film for organic layer thermal transfer is brought into close contact with the substrate thus prepared, and scanned from the film side with, for example, ultraviolet laser light. The scan width can be controlled from several μm to several mm or more depending on the slit inserted in the optical path, the imaging lens, the beam profile, or the number of scans. The scanning method may be a case where the sample stage is scanned or a case where the laser light itself is scanned. When the donor film is removed from the substrate by a mechanical method after thermal transfer, a transfer film is produced on the substrate having high thermal conductivity, and no transfer film is produced on the organic film having low thermal conductivity. In this way, the transfer film can be easily formed in a predetermined pattern in a self-aligning manner.
[0013]
The method for forming the organic film in a predetermined pattern can be appropriately selected depending on the type of the organic film. When the organic film is made of a polymer film, it can be formed into a predetermined pattern by a lithography technique in which the organic film is formed into an arbitrary shape by a light source such as light (ultraviolet light, etc.), an electron beam, an ion beam, or an X-ray.
[0014]
In the case of a low molecular weight material, for example, an ultraviolet ray with a mask is used to create an irradiation area of an arbitrary pattern shape, and the low molecular weight material is used as a self-assembled monomolecular (SAM) film only on the part exposed to the ultraviolet light. It can be formed in a predetermined pattern by growing. In this case, since pattern processing after film formation is not required, an arbitrary shape can be accurately produced. Further, the surface of the substrate that has been irradiated with ultraviolet rays has a contact angle of water as close as possible to 0 °, and becomes a surface that is very easy to apply. The main factor for such a hydrophilic surface is considered to be that a high-density hydroxyl group covers the substrate surface from the measurement result of the contact angle. In the present invention, it is preferable to use a material having a molecular weight of 200 to 500 as the low molecular weight material.
[0015]
As the low molecular weight material, an organic molecule having a covalent bond group composed of a chlorosilyl group at the terminal can be used. If this organic molecule is used, the covalent bond group makes use of the fact that the hydroxyl group density on the surface of the substrate that has been irradiated with ultraviolet rays is increased. Can be done. The molecular structure of the organic molecule used is, for example, the general formula (1) V- (CH₂)_x-W- (CH₂)_y-SiCl_nX_3-n(Where n is an integer of 1 to 3, x and y are positive integers, and x + y is most easily handled in the range of 5 to 18. V is —CH._Three, -CH = CH₂, -COOH, halogen atom, -CO₂CH_Three, -SiCl_nX_3-n, -Si (OR)_nX_3-n, -CN and the like. W is CH₂, Alkenylene, alkynylene, phenylene, pyridylene, chenylene and the like. X is a lower alkyl group, especially CH_Three, C₂H_FiveIs preferred).
[0016]
Another low molecular weight material that utilizes the increased hydroxyl group density on the substrate surface is an organic molecule having a covalent bond group consisting of a lower alkoxysilyl group at the terminal. The molecular structure of the organic molecule used is the general formula (2) V- (CH₂)_x-W- (CH₂)_y-Si (OR)_nX_3-nIt is represented by R is a C1-C6 lower alkyl group (preferably a methyl group or an ethyl group).
Still another low molecular weight material utilizing the fact that the hydroxyl group density on the substrate surface is high is an organic molecule having a phosphonic acid group at the terminal. The molecular structure of the organic molecule used is the general formula (3) SH- (CH₂)_x-PH₂O_ThreeIt is represented by x is a positive integer, and about 5 to 18 is the easiest to handle.
[0017]
Another low molecular weight material that utilizes the increased hydroxyl group density on the substrate surface includes organic molecules having a carboxyl group at the terminal. The molecular structure of the organic molecule used is the general formula (4) Z- (CH₂)_xExpressed as -COOH. x is a positive integer, and about 5 to 18 is the easiest to handle. Z is -SH or -CH_ThreeEtc. are used.
A laminated film in which a monomolecular film made of an organic molecule having a phosphonic acid group or a carboxyl group at the end is laminated several times each or alternately via a metal ion selected from the group consisting of Zr, Hf, Cu or Zn It is good.
Further, the organic film may serve as a spacer for preventing the first electrode and the second electrode from being in electrical contact.
[0018]
The method for producing an organic light emitting device of the present invention is preferably applied to a method for producing an organic EL device. In the following, an organic EL element is taken as an example, and a method for manufacturing an organic light emitting element by a thermal transfer method will be described. First, the method of the present invention can be applied to an organic EL device in which light emission is extracted from either the substrate side or the second electrode side. When light emission is taken out from the substrate side, a transparent material is used for the substrate and the first electrode, and when light emission is taken out from the second electrode side, a transparent material is used for the second electrode.
[0019]
In the thermal transfer method, a layer of an organic EL element for which thermal transfer is desired is formed on a donor substrate for thermal transfer. The donor substrate is not particularly limited, and a known donor substrate such as a resin film can be used. On this donor substrate, a known heat propagation layer, photothermal conversion layer, and transfer auxiliary layer (a layer made of a material having a lower melting point than the material constituting the second electrode) are formed in advance in order to improve transfer efficiency. May be.
[0020]
A second electrode is formed on the donor substrate. The formation method varies depending on the material used, and examples thereof include a vapor deposition method, an electron beam method, a sputtering method, and a spray method. Further, an organic layer including at least a light emitting layer is formed on the second electrode. In the case of a full-color organic EL element, the light emitting layer may be separately applied to each color of RGB. In this case, three colors of light emitting layers may be formed on one donor substrate, or three donor substrates may be used for each color. Examples of the organic layer other than the light emitting layer include a hole transport layer, a hole injection layer, an electron transport layer, and an electron injection layer. Examples of the method for forming the organic layer include a vapor deposition method, a spin coating method, a printing method, and an ink jet method.
[0021]
As a material used for the light emitting layer, for example, tris (8-hydroxynato) aluminum complex (Alq_Three), Bis (2-methyl-8-quinolinolato) (p-phenylphenolate) aluminum (BAlq), benzoxazole compounds, benzothiazole compounds, and the like. In addition, a dopant can be added to change the emission color or improve the characteristics. Examples of such a dopant include quinacridone, rubrene, 4-dicyanomethylene-2-methyl-6- (p-dimethylaminosrityl) -4H-pyran (DCM), and a coumarin derivative.
[0022]
Examples of materials used for the hole transport layer and the hole injection layer include N, N′-diphenyl-N, N ′ (3-methylphenyl) -1,1′-diphenyl-4,4′-diamine ( TPD), N, N′-diphenyl-N, N′-bis (α-naphthyl) -1,1′-biphenyl-4,4′-diamine (α-NPD), copper phthalocyanine (CuPc), oxadiazole , Pyrazoline compounds, hydrazone compounds, and the like.
Examples of materials used for the electron transport layer and the electron injection layer include oxadiazole derivatives, tris (8-hydroxynato) aluminum complexes (Alq_Three), Triazole derivatives and the like.
By the above method, a donor substrate (donor film) on which layers constituting an organic EL element are laminated can be obtained.
[0023]
Next, the donor film and the substrate are bonded and thermally transferred, and the donor substrate is peeled off. That is, the donor substrate and the substrate are bonded so that both substrates are on the outside, the layer formed on the donor substrate is thermally transferred onto the uppermost layer formed on the substrate side, and the donor substrate is peeled off.
The heat source of the thermal transfer method is not particularly limited as long as the second electrode and the organic layer formed on the donor substrate side can be thermally transferred to the substrate side. More specifically, it is preferable to apply locally strong energy to obtain a high-definition pattern, and laser light, particularly ultraviolet laser light and YAG laser light can be used effectively. Further, a more complete line pattern can be obtained by using continuous wave laser light.
[0024]
This thermal transfer method will be specifically described.
First, the donor substrate and the substrate are bonded so that the first electrode and the organic layer are in contact with each other. At this time, it is preferable to deaerate by bonding the bonded material with a roller or the like so that no bubbles remain in the bonded region. A vacuum laminating method is effective for removing bubbles. Next, laser light is irradiated. In the past, this laser beam was irradiated in a pattern that desired thermal transfer. However, in the present invention, an organic film is formed on the surface of the substrate to be thermally transferred. May be. Moreover, you may irradiate in pattern shape like the past.
By peeling the donor substrate after irradiation, the second electrode and the organic layer are thermally transferred onto the substrate on which the first electrode is formed, and an organic EL element is obtained.
[0025]
In the above method, the organic layer and the second electrode are thermally transferred at the same time. However, the organic layer and the second electrode may be separately thermally transferred. When the second electrode is separately formed by thermal transfer or another method, a second electrode buffer layer may be provided on the organic layer on the second electrode side.
[0026]
【Example】
Example 1
An ITO film having a thickness of about 100 nm, which is an anode (first electrode), is laminated on a glass substrate having a thickness of about 1.0 μm. On a glass substrate including an ITO film, an acrylic resin (PC409 manufactured by JSR) was applied as a kind of general-purpose polymer by spin coating. The spin coating conditions were 2000 rpm / 30 seconds and prebaked at 100 ° C./100 seconds to produce an organic film having a thickness of about 0.1 μm. 100mJ / cm through a mask with a predetermined pattern using an exposure tool²After exposure at (365 nm), development was performed for 60 seconds with a developer. Thereafter, ultrapure water was washed at room temperature for 60 seconds, and further heated in a clean oven at 220 ° C./60 minutes. Depending on the shape of the mask at the time of exposure, various shapes can be patterned, but this time, a dot pattern with a resolution of 2.0 × 2.0 μm was produced.
In addition to light, lithography technology is progressing with the use of electron beams and X-rays as light sources, and it is possible to meet the design rule of 0.15 μm, which can further improve the resolution of lithography. Is possible.
[0027]
The donor film used this time is about 1 nm of LiF (lithium fluoride) as a cathode buffer layer on a support (hereinafter referred to as base film) on which a heat propagation layer (also used as a release layer) is formed on a PET film. After the lamination with a thickness of quinolyl aluminum complex (hereinafter referred to as Alq)_Three) And N, N′-diphenyl-N, N′-bis (α-naphthyl) -1,1′-biphenyl-4,4′-diamine (hereinafter α-NPD) as a hole injection layer with a thickness of 30 nm, respectively. The organic layer was formed by vapor deposition. For vapor deposition, the base vacuum in the vapor deposition system is 5.0 × 10.^-7A quartz oscillator monitor was used for controlling the film thickness.
[0028]
The donor film is brought into close contact with a substrate provided with an ITO film, and scanned from the PET film side with, for example, an ultraviolet laser. The scanning method may be either the case of scanning the sample stage or the case of scanning the laser itself, but this time the sample stage was scanned at 0.1 to 3.0 m / sec. When the base film is mechanically removed from the substrate after thermal transfer, a transfer film is produced on the substrate with high thermal conductivity, and a transfer film (organic layer) is produced on the organic film made of acrylic resin with low thermal conductivity. Not (FIG. 1). The layer structure of the transfer film on the organic film and on the substrate without the organic film was confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer. In FIG. 1, 1 is a transfer film, 2 is an acrylic resin, 3 is an ITO film, and 4 is a glass substrate.
[0029]
Example 2
The versatile polymer described in Example 1 is deposited on the ITO film patterned with hydrochloric acid + ferric chloride or HBr (hydrogen bromide), especially at the edge of the ITO film, and is deposited as a cathode. The role of preventing electrical contact with the electrode material is also added. After applying an acrylic resin on the substrate having the patterned ITO film, the same photolithography process as in Example 1 was performed so that the polymer remained selectively only at the edge portion of the ITO film. The same organic layer as in Example 1 was formed on this substrate by a thermal transfer method, and an Al electrode (second electrode) was deposited as a cathode to a thickness of 100 nm. As a result of electrical testing, it was found that there was no current flowing between the Al electrode and the ITO film (Figure 2). Furthermore, the pattern formation of the transfer film on the ITO film and the acrylic resin at the edge of the ITO film and the state after the thermal transfer were confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer. In FIG. 2, 5 means an Al electrode.
[0030]
Example 3
Instead of the acrylic resin of Example 1, an arbitrary pattern shape using an organic low molecular weight material was produced (FIG. 3). Using the mask 7 having a line and space with a period of 3 μm at the time of ultraviolet irradiation, selective ultraviolet irradiation was performed on the substrate provided with the ITO film. The irradiation conditions are an excimer lamp 6 and an output of 10 mW / cm²The irradiation time is about 10 minutes. The substrate irradiated with ultraviolet rays had a contact angle of water as close as possible to 0 °, and formed a surface that was very easy to apply. On the other hand, the ITO surface that was not irradiated with ultraviolet rays had a water contact angle of about 90 °, indicating a hydrophobic surface state. By using this substrate as a SAM film growth substrate, an organic film made of a SAM film that is selectively adsorbed to the ultraviolet irradiation site was formed.
In this example, a film made from an OTS (octadecyltrichlorosilane) solution was used as the SAM film. Thereafter, the transfer film pattern was formed in the same manner as in Example 1. The state of the transfer film was confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer.
[0031]
Example 4
An organic film having an arbitrary pattern by adsorbing an organic molecule having a covalent bond group composed of a chlorosilyl group at a terminal selectively bonded to a hydroxyl group when producing a patterned substrate using the SAM film described in Example 3 Was made. First, only a specific area on the ITO substrate surface was irradiated with ultraviolet rays using a mask having a line and space with a period of 3 μm, and the substrate was immersed in a 1 mM OTS solution prepared in advance for about 15 minutes. . OTS solution is octadecyltrichlorosilane [CH_Three(CH₂)₁₇SiCl_Three, OTS] was prepared by mixing 79 μl with n-hexadecane; 70 ml + carbon tetrachloride; 30 ml. Usually, the OTS solution is made with a molecular concentration that is excessive compared to the uniform coverage of the substrate with a monomolecular film thickness, and excess OTS molecules that cannot bind to the substrate are almost completely removed from the solution when the substrate is removed from the solution. However, it may remain on the OTS monolayer by physical adsorption. For this purpose, the substrate whose surface was covered with SAM molecules was washed with chloroform for 3 minutes and then blown with Ar gas and dried.
CH_Three(CH₂)₁₇SiCl₂A state in which a monomolecular film made of O is formed through O is shown in the following formula (Formula 1).
CH_Three-(CH₂)₁₇-SiCl_Three+ (-OH)
→ CH_Three-(CH₂)₁₇-SiCl₂-O- + HCl (Chemical formula 1)
[0032]
Thereafter, Si-Cl groups of unreacted OTS molecules also react with moisture in the atmosphere (or in solution) to form Si-OH groups. This is shown in the following formula (Formula 2).
CH_Three-(CH₂)₁₇-SiCl₂-O- + 2H₂O
→ CH_Three-(CH₂)₁₇-Si (OH)₂-O- + 2HCl (Chemical formula 2)
[0033]
Next, the silanol group (—SiOH) is dehydrated and condensed with the adjacent silanol group to form a bond represented by the following formula (Formula 3).
n [CH_Three-(CH₂)₁₇-Si (OH)₂-O-]
→ n [CH_Three-(CH₂)₁₇-SiO₂-O-] + nH₂O
The coating was confirmed by ellipsometry, and the OTS molecules were selectively adsorbed on the substrate at a thickness of about 20 nm. This makes CH on the substrate surface._Three(CH₂)₁₇A monomolecular film made of SiO was formed through O. When a transfer film was produced on the thus produced substrate by the same method as in Example 1, a transfer film was confirmed at the exposed portion of the ITO substrate, but no transfer film was confirmed on the organic film ( FIG. 4). The state of the transfer film was confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer. In FIG. 4, 9 denotes an organic film made of a SAM film having a siloxane bond.
[0034]
Example 5
The OTS molecule used in Example 4 was converted to octadecyltrimethoxysilane [CH_Three(CH₂)₁₇Si (OCH_Three)_Three] A similar experiment was conducted except that it was replaced with a molecule. Specifically, the same procedure as in Example 4 was performed except that the substrate was immersed in an octadecyltrimethoxysilane solution having a concentration of 1 mM prepared in advance for about 30 minutes. Except that the dehydrochlorination reaction in Example 4 is changed to a dealcoholization reaction, the reaction proceeds in the same manner as the chemical reaction formulas (Chemical Formulas 1 to 3) (Chemical Formulas 4 to 6), and the monomolecular film shown in the chemical reaction formula (Chemical Formula 6) Formed on the substrate. A monomolecular film composed of octadecyltrimethoxysilane molecules was formed in the ultraviolet irradiation region. Thereafter, it was washed with chloroform for 3 minutes and then blown with Ar gas and dried.
CH_Three(CH₂)₁₇Si (OCH_Three)_Three+ (-OH)
→ CH_Three-(CH₂)₁₇Si (OCH_Three)₂-O- + CH_ThreeOH
[0035]
Thereafter, Si-Cl groups of unreacted OTS molecules also react with moisture in the atmosphere (or in solution) to form Si-OH groups. This is shown in the following formula (Formula 5).
CH_Three-(CH₂)₁₇-Si (OCH_Three)₂-O- + 2H₂O)
→ CH_Three-(CH₂)₁₇-Si (OH)₂-O- + 2CH_ThreeOH
[0036]
Next, the silanol group (—SiOH) is dehydrated and condensed with the adjacent silanol group to form a bond represented by the following formula (Formula 6).
n [CH_Three-(CH₂)₁₇-Si (OH)₂-O]
→ n [CH_Three-(CH₂)₁₇-SiO₂-O] + nH₂O
The coating was confirmed by ellipsometry, and octadecyltrimethoxysilane molecules were selectively adsorbed on the substrate at a thickness of about 25 nm. When a transfer film was produced on the substrate thus produced, the transfer film was confirmed at the exposed portion of the substrate, but no transfer film was confirmed on the organic film (FIG. 4). The state of the transfer film was confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer.
[0037]
Example 6
The OTS molecule used in Example 4 was converted to mercaptophosphonic acid; SH (CH₂)_FourPH₂O_ThreeA similar experiment was performed except that the molecule was replaced. Specifically, the substrate was immersed in a mercaptophosphonic acid solution prepared in advance. Mercaptophosphonic acid solution is a kind of linear organic molecule in pure ethanol solvent, and has -SH group at the end and -PH at the opposite end.₂O_ThreeMercaptophosphonic acid molecules characterized by having a group were prepared by developing at a concentration of 1 mM. By leaving it in the mercaptophosphonic acid solution for 30 minutes, the mercaptophosphonic acid molecules having a monomolecular thickness were selectively adsorbed on the substrate at a thickness of about 0.8 nm. The coating was confirmed by ellipsometry. When a transfer film was produced on the substrate provided with the organic film thus produced, the transfer film was confirmed on the exposed portion of the substrate, but no transfer film was confirmed on the organic film (FIG. 5). The state of the transfer film was confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer. In FIG. 5, 10 denotes an organic film made of a SAM film of mercaptophosphonic acid molecules.
[0038]
Example 7
A similar experiment was conducted except that the OTS molecule used in Example 4 was replaced with a 16-bisphosphonic acid molecule. Specifically, by leaving the substrate in a 16-bisphosphonic acid solvent prepared in advance for about 30 minutes, 16-bisphosphonic acid molecules with a monomolecular film thickness can be irradiated with ultraviolet rays through the mask. The irradiated substrate surface was covered. 16-Bisphonic acid solution is a kind of linear organic molecule in pure ethanol solvent.₂O_Three16-bisphosphonic acid O characterized by having a group_ThreeH₂P (CH₂)₁₆PH₂O_ThreeWas prepared by developing at a concentration of 1 mM. Thereafter, for rinsing, the substrate was immersed in pure ethanol and subjected to ultrasonic cleaning. Furthermore, it was dried by Ar gas blow. The organic film was confirmed by ellipsometry, and 16-bisphosphonic acid molecules were selectively adsorbed on the substrate at a thickness of about 2 to 3 nm. When a transfer film was produced on the substrate provided with the organic film thus produced, the transfer film was confirmed on the exposed portion of the substrate, but no transfer film was confirmed on the organic film (FIG. 6). The state of the transfer film was confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer. In FIG. 6, 11 denotes an organic film made of a SAM film of 16-bisphosphonic acid molecules.
[0039]
Example 8
As in Example 7, after forming a 16-bisphosphonic acid molecular monomolecular film on the substrate surface, this monomolecular film was used as the first layer, and a substrate provided with the monomolecular film was separately prepared.²⁺1 mM zinc perchlorate hexahydrate that produces ions; Zn (ClO_Four)²・ 6H₂It was left to stand in O aqueous solution for 5 minutes. By this treatment, -PH of two adjacent 16-bisphosphonic acid molecules₂O_ThreeBase and Zn²⁺The ions react to produce a substrate whose surface of the monomolecular film is covered with Zn. Thereafter, the substrate was ultrasonically cleaned in pure ethanol to rinse excess zinc perchlorate hexahydrate.
[0040]
This substrate was allowed to stand again in a 16-bisphosphonic acid solution for about 30 minutes to form a second 16-bisphosphonic acid monomolecular thin film. The coating was confirmed by ellipsometry, and the multilayer film (organic film) composed of two molecules of 16-bisphosphonic acid and Zn was selectively adsorbed on the substrate at a thickness of about 4.6 nm.
By repeating this process, it is possible to create a cumulative film (organic film) with an arbitrary film thickness (substantially an integral multiple of the monomolecular film thickness 2.3 nm) that is precisely controlled at the molecular level. . Each metal ion solution is 1 mM ZrOCl.₂Or HfOCl₂In the same way as described above, the multilayer film composed of two molecules of 16-bisphosphonic acid and Zr and Hf is selectively adsorbed on the substrate, and an ellipso film is formed with a thickness of about 4.6 nm. Confirmed by meter.
[0041]
When a transfer film was prepared on the substrate thus prepared, the transfer film was confirmed at the exposed base portion, but no transfer film was confirmed on the organic film (FIG. 7). The state of the transfer film was confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer. In FIG. 7, 12 denotes an organic film composed of a multilayer film composed of two molecules of 16-bisphosphonic acid and Zn.
[0042]
Example 9
Further, a laminated film was formed in the same manner as the 16-bisphosphonic acid laminated film of Example 8 except that a mercaptoacetic acid solution was used. Specifically, a mercaptoacetic acid solution is a kind of linear organic molecule in a pure ethanol solvent and has a 1-mM mercaptoacetic acid molecule having a -SH group at the end and a carboxyl group at the opposite end. Prepared by developing at a concentration of. First, the substrate irradiated with ultraviolet rays using a mask having a line and space with a period of 3 μm is left in a mercaptoacetic acid solution for 30 minutes, and ultrasonically washed in pure ethanol to remove excess mercaptoacetic acid molecules. The first layer of mercaptoacetic acid monomolecular film was selectively adsorbed at a thickness of about 1.2 nm (FIG. 8). The coating was confirmed by ellipsometry. In FIG. 8, 13 denotes a mercaptoacetic acid monomolecular film.
[0043]
The substrate provided with the first layer of mercaptoacetic acid monomolecular film was allowed to stand in a separately prepared 1 mM Cu acetate solution for 5 minutes and then immersed again in the mercaptoacetic acid solution for 30 minutes. By this treatment, -SH group of two molecules of mercaptoacetic acid and Cu ions of Cu acetate were sulfide-bonded, and a substrate covered with a bimolecular-thick mercaptoacetic acid monomolecular film was formed. The substrate was then ultrasonically cleaned in pure ethanol to rinse excess mercaptoacetic acid molecules, Cu acetate molecules, and Cu ions. Furthermore, it was dried with Ar blow. The coating was confirmed by ellipsometry, and the multilayer film composed of two mercaptoacetic acid molecules and Cu was selectively adsorbed on the substrate at a thickness of about 4.6 nm. When a transfer film was produced on the substrate thus produced, the transfer film was confirmed on the exposed portion of the substrate, but no transfer film was confirmed on the organic film. The state of the transfer film was confirmed using an Auger electron spectrometer, an atomic force microscope, and an energy spectrometer.
[0044]
Example 10
Among the organic EL elements described in Examples 1 to 9, the organic EL elements prepared in Example 1, Example 4, and Example 7 are all 4-5 (mA / cm²) 350-400 (cd / cm)²) Was obtained (FIG. 9).
[0045]
【The invention's effect】
According to the present invention, it is possible to overcome the limitations of element separation by masks and diversify transfer film patterns, which are problems in the development of conventional organic EL elements, and further solve the problem by lithography and self-organized molecules. Since this can be achieved by application of a film manufacturing technique, the process at the time of element manufacturing can be simplified. Further, since the organic insulating film can be formed in an arbitrary shape, the application range is further expanded, and new elements having various structures can be created.
[Brief description of the drawings]
FIG. 1 is a schematic view of an organic EL device obtained by the production method of the present invention by a thermal transfer method patterned with an acrylic resin.
FIG. 2 is a schematic cross-sectional view of an organic EL device according to the manufacturing method of the present invention, illustrating a configuration for preventing current leakage between electrodes.
FIG. 3 is a schematic view for explaining a method of forming an ultraviolet irradiation region using a mask in the manufacturing method of the present invention.
FIG. 4 is a schematic diagram for explaining a transfer film patterning method using a SAM film having a siloxane bond in the manufacturing method of the present invention.
FIG. 5 is a schematic view for explaining a patterning method of a transfer film using a mercaptophosphonic acid monomolecular film in the production method of the present invention.
FIG. 6 is a schematic view for explaining a transfer film patterning method using a 16-bisphosphonic acid monomolecular film in the production method of the present invention.
FIG. 7 is a schematic diagram for explaining a patterning method of a transfer film using a 16-bisphosphonic acid monomolecular film in the production method of the present invention.
FIG. 8 is a schematic view for explaining a patterning method of a transfer film using a mercaptophosphonic acid molecular film in the production method of the present invention.
FIG. 9 is a graph showing current density-luminescence luminance characteristics of an organic EL device obtained by the production method of the present invention.
[Explanation of symbols]
1 Transfer membrane
2 Acrylic resin
3 ITO film
4 Glass substrate
5 Al electrode
6 Excimer lamp
7 Mask
8 UV irradiation site
9 Organic film consisting of SAM film with siloxane bond
10 Organic film consisting of SAM film of mercaptophosphonic acid molecule
11 Organic film composed of SAM film of 16-bisphonic acid molecule
12 16-Bisphosphonic acid 2 molecule and Zn multi-layer organic film
13 Mercaptoacetic acid monolayer

Claims (6)

On at least a substrate, a first electrode, a manufacturing method of a light emitting element having an organic layer and a second electrode including a light emitting layer, from the first electrode on a substrate having a first electrode 10 ^{- 2} and 10 ^- An organic film with a predetermined pattern of low thermal conductivity is formed in the range of ⁵ cal / cm · s · ° C, an organic layer is placed on the first electrode and the organic film, and the organic layer is transferred onto the first electrode. the organic film in alignment with the first electrode on the first electrode by a thermal transfer method under conditions not transferred consists in forming the organic layer,
An organic film is formed as a self-assembled monomolecular film in which ultraviolet rays are irradiated onto a substrate through a mask having a predetermined pattern and a low molecular material is selectively adsorbed only in the ultraviolet irradiation region. Manufacturing method of electroluminescent element.   The manufacturing method according to claim 1, wherein the organic film is positioned between both electrodes so as to prevent a short circuit between the first electrode and the second electrode. The production method according to claim 1 or 2 , wherein the monomolecular film is obtained by adsorbing an organic molecule having a covalent bond group composed of a chlorosilyl group or a lower alkoxysilyl group at a terminal. The production method according to claim 1 or 2 , wherein the monomolecular film is obtained by adsorbing an organic molecule having a phosphonic acid group or a carboxyl group at a terminal. The organic film is a monomolecular film made of an organic molecule having a phosphonic acid group or a carboxyl group at the terminal, and is alternately or alternately plural times via a metal ion selected from the group consisting of Zr, Hf, Cu or Zn. The manufacturing method of Claim 4 which consists of a laminated film laminated | stacked.   The manufacturing method according to claim 1 or 2, wherein the organic film is a polymer film selected from an acrylic resin, an epoxy resin, a urethane resin, and a xylene resin.

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